Abstract
A protective cap device for a milling blank, with a retaining element (24) or retaining extension (26) with which the milling blank (1) can be clamped, in particular in a clamping holder of a dental milling machine, and with a central channel (12) which extends over and/or passes through at least 70% of the length of the blank (1), is provided. The channel (12) terminates at or in the retaining element (24) or extension (26). A central pin (4) extends in the channel (12) and is either fixed or movably mounted in the channel (12), It is provided that a protective cap (10) covers an end face (20), which is opposite the retaining element (24) or retaining extension (26), of the milling blank (1).
Claims
1. A protective cap and milling blank assembly comprising a milling blank (1) and a protective cap (10), wherein the milling blank (1) comprises a retaining element (24) or a retaining extension (26) with which the milling blank (1) is configured for clamping in a clamping holder of a dental milling machine, a central channel (12) which extends over at least 70% of the length of the blank (1) and/or passes therethrough, wherein the channel (12) ends at or in the retaining element (24) or retaining extension (26), a central pin (4) which extends in the channel (12), wherein the central pin (4) is either fixed or movably mounted in the channel (12), and wherein the protective cap (10) covers an end face (20), which lies opposite the retaining element (24) or the retaining extension (26), of the milling blank (1).
2. The protective cap and milling blank assembly according to claim 1, wherein the milling blank (1) comprises a truncated cone portion extending over more than 30% of the length of the blank at a part of the blank remote from the retaining element (24) or retaining extension (26).
3. The protective cap and milling blank assembly according to claim 1, wherein the central pin (4) comprises a thread (36) on the end face (20) of the blank (1) which engages with a nut and the protective cap (10) covers the nut.
4. The protective cap and milling blank assembly according to claim 1, wherein the protective cap (10) is formed from an elastic material and covers an end face (20) on the truncated cone side, of the blank.
5. The protective cap and milling blank assembly according to claim 4, wherein the elastic material comprises an elastomer and the protective cap covers the end face (20) on the truncated cone side by more than 50%.
6. The protective cap and milling blank assembly according to claim 1, wherein the protective cap (10) is formed from solid material comprising a plastic and/or metal, and bears at least partially against the central pin (4) and/or an implant connection (14, 28 or 30).
7. The protective cap and milling blank assembly according to claim 1, wherein a seal is provided between the central pin (4) and the protective cap (10) at the end face (20) and/or between the central pin (4) and the milling blank (1) at the retaining extension side.
8. The protective cap and milling blank assembly according to claim 1, wherein the central pin (4) is protected from being pulled out by a thickening at one end, a sealing lip or by screws.
9. A milling blank comprising a retaining element (24) or retaining extension (26), by which the milling blank (1) can be clamped in a clamping holder of a dental milling machine, a central channel (12) which extends over at least 70% of the length of the blank (1) and/or passes through it, the channel (12) ending at or in the retaining element (24) or retaining extension (26), a central pin (4) which extends in the channel (12), the central pin (4) being fixed in the channel (12), and a protective cap (10) covers an end face (20), which is opposite the retaining element (24) or retaining extension (26), of the milling blank (1) and seals the latter, the central pin (4) and thus the opening of the channel (12).
10. The milling blank according to claim 9, wherein an implant connection (14, 28 or 30) comprising an outer hex (14), an inner hex (28) or a cone (30), is formed on the end face (20) of the blank, which is covered and sealed by the protective cap (10), and wherein the protective cap (10) is fastened to the central pin (4) by frictional engagement of the sealing ring of the protective cap (10) and of the milling blank (1) and/or by a thread (36).
11. The milling blank according to claim 10, wherein the central pin (4) has the thread (36) on the end face (20) of the blank which engages with a nut and the protective cap (10) covers the nut.
12. The milling blank according to claim 11, wherein the central channel (12) has an internal thread at the retaining extension side end and/or at the end face (20) and/or along the entire central channel and the central pin (4) has an external thread matching the thread of the central channel.
13. The milling blank according to claim 12, wherein a seal is provided between the central pin (4) and the protective cap (10) at the end face (20) and/or between the central pin (4) and the milling blank (1) at the retaining extension side end.
14. A method for producing a milling blank for milling a dental restoration part comprising providing a blank (1), creating a central channel (12) in the blank, which ends at or in a retaining element (24) or retaining extension (26), at which the milling blank (1) is configured for clamping in a milling machine, wherein more than 70% of a length of the blank (1) is partially or fully penetrated with the central channel (12), introducing a central pin (4) into the central channel (12), the central pin (4) being fixed in the channel (12) at an end having the retaining element or extension, and wherein the central pin (4) and an end face (20) which is opposite the retaining element (24) or retaining extension (26) are covered, by a protective cap (10) which is attached in a sealing manner to the end face.
15. The method according to claim 14, wherein the central pin (4) and the end face (20) are covered by the protective cap to at least 50%.
16. The method according to claim 14, wherein the milling blank (1) is partially manufactured and an implant connection (14, 28 or 30) extends on the end face, which is also covered by the protective cap (10).
17. The method according to claim 14, wherein the milling blank (1), after being equipped with the central pin (4) and the protective cap (10), is clamped in a clamping holder of a dental milling machine and the dental milling machine mills the milling blank while the central pin (4) extends in the channel (12) and while the protective cap (10) covers part of the end face (20) of the milling blank (1).
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0060] Further advantages, details and features will be apparent from the following description of several embodiments of the invention with reference to the drawings.
[0061] FIG. 1A shows a schematic representation of the lateral cross-section of a partially fabricated milling blank according to the invention in a first embodiment.
[0062] FIG. 1B shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0063] FIG. 1C shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0064] FIG. 2 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0065] FIG. 3 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0066] FIG. 4 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0067] FIG. 5 shows a schematic representation of the manufacturing process of a dental restoration part from a partially manufactured milling blank according to the invention.
[0068] FIG. 6 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0069] FIG. 7 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention.
[0070] FIG. 8 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank according to the invention after the milling process.
DETAILED DESCRIPTION
[0071] FIG. 1A shows a schematic representation of the lateral cross-section of a partially manufactured milling blank 1 according to the invention with central pin 4 and pin counter element 5, protective cap 10, schematically indicated implant-supported dental restoration part 8 and an external hex implant connection 14. This variant of the partially manufactured milling blank is a one-piece embodiment of a blank 1 according to the invention. The embodiment of an implant-supported dental restoration part 8 is shown schematically with dashed lines therein. In this embodiment, fixation to a common retaining material is provided by means of adhesive fixation. One could also say that the milling blank itself can thus serve as a retaining element. An embodiment of an implant-supported dental restoration part 8 created with CAD/CAM software is shown as a dashed tooth outline and connected to the external hex implant connection 14. In this embodiment, the central channel 12 passes through the entire length of the partially fabricated blank 1.
[0072] The base body 2 of the partially fabricated milling blank has a basic conical geometry, whereby the front side 18 has a larger diameter than the base 20 in order to adapt to the natural geometry of the occlusal and gingival tooth form areas. By removing the indicated excess areas 6 of the base body, the shape of a truncated cone 16 is formed. Of course, it is also possible to design and pre-sinter the shape of a truncated cone 16 already during the production of the blank, without the suggested excess areas 6. This special shape is close to the natural tooth geometry and thus avoids unnecessarily long milling processes. The dome-like protective cap 10 is attached to the truncated cone end or base 20 of the milling blank 1. In this embodiment, the central pin 4 fills the channel bore 12 with a snug fit. The pin counter element 5 serves to fix the central pin 4 to the retaining extension side end of the milling blank 1.
[0073] FIG. 1B shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, protective cap 10, schematically indicated implant-supported dental restoration part 8, an external hex implant connection 14 and a further embodiment of a retaining element 24, which is attached to or partially in the partially manufactured milling blank. This variant of the partially manufactured milling blank is a multi-part, in particular two-part, embodiment of a partially manufactured blank 1 according to the invention as shown in FIG. 1A. In this embodiment, a fixing to a common retaining material is provided by means of an attached retaining extension 26 or retaining element 24. This can be accommodated in the recess 22 provided for this purpose in the base body 2 of the partially finished milling blank. In this embodiment, the central channel 12 does not run through the entire length of the partially finished blank 1. It ends at the point at which the attached retaining element 24 is inserted into the recess 22 provided in the base body 2 of the partially finished milling blank.
[0074] FIG. 1C shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, protective cap 10, schematically indicated implant-supported dental restoration part 8, an external hex implant connection 14 and a retaining extension 26 as part of the basic body 2 of the partially manufactured milling blank. This variant of the partially manufactured milling blank is a one-piece version of a blank 1 according to the invention, like the one shown in FIG. 1A, but in a further embodiment. In this embodiment, fixing to a common retaining material is provided by means of an integrated retaining extension 26. This is part of the base body 2 of the partially manufactured milling blank. In this embodiment, the central channel 12 again runs through the entire length of the partially finished blank 1.
[0075] FIG. 2 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, protective cap 10, schematically indicated implant-supported dental restoration part 8 according to FIG. 1A, but with an internal hex implant connection 28.
[0076] FIG. 3 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, protective cap 10, schematically indicated implant-supported dental restoration part 8 according to FIG. 1A, but with a conical implant connection 30.
[0077] FIG. 4 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, protective cap 10 with threaded fixing 36, schematically indicated implant-supported dental restoration part 8 and an external hex implant connection 14. In this embodiment, a sealing lip 32 is inserted between the central pin 4 and the central channel 12 at the retaining extension side end, which seals the central channel 12 against contamination with dust or chips that occur during the milling process. In this embodiment, the central channel 12 passes through the entire length of the partly finished blank 1. Furthermore, an external thread is formed at the end on the truncated cone side or at the base 20 of the central pin 4, which is formed to match the thread 36 of the protective cap 10, so that these two threads can be screwed into one another. On the one hand, this allows the protective cap 10 to be fixed and, on the other hand, it prevents the central pin 4 from being pulled out in the direction of the retaining extension/face 18. In this embodiment, the protective cap 10 is hollow but thick-walled and is sealed to the base body 2 of the partially manufactured milling blank by means of a design 34 in such a way that it seals the protective cap against an undercut of the partially manufactured blank. This design 34 enables the protective cap 10 to be fastened to the base body 2 of the partially finished milling blank and ensures optimum sealing against possible impurities.
[0078] FIG. 5 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, protective cap 10 with friction fixation 38, schematically indicated implant-supported dental restoration part 8 and an external hex implant connection 14. This embodiment corresponds to a modification of the variant shown in FIG. 4. In this embodiment, an external thread is formed on the truncated cone end or base 20, at the level of the implant connection, on the central pin 4, which is formed to match the thread of the nut of the external hex implant connection 14, so that these two threads can be screwed into each other. This prevents the central pin 4 from being pulled out in the direction of the retaining extension/face 18. In this embodiment example, the protective cap 10 is hollow but thin-walled and is sealed to the base body 2 of the partially finished milling blank by means of a design 34 such that it seals the protective cap against an undercut 33 of the partially finished blank. During the milling process, a sovereign zone 35 is left unmachined around this fixing as a CAD/CAM protective area. This is indicated in FIG. 5 as a rectangle around such a design 34 of the sealing lip. In addition to such a fixing by means of a special design 34 of the sealing lip, the protective cap 10 is fixed to the central pin 4 by means of a friction fixing 38. The central pin 4 penetrates the recess of the protective cap 10, which is preferably made of elastic material, or penetrates it completely and is fixed there by means of frictional locking.
[0079] FIG. 6 shows a schematic partial representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention with central pin 4, sealing lip 32, schematically indicated implant-supported dental restoration part 8 and a schematic representation of a milling head 44. In this embodiment, a common milling head of a manufacturing device with milling tip 42 is shown schematically. In this illustration, the protective cap and the implant connection are only sketchily indicated at the end of the truncated cone or at the base 20 of the basic body 2 of the partially manufactured milling blank.
[0080] FIG. 7 shows a schematic representation of the lateral cross-section of a further embodiment of a partially manufactured milling blank 1 according to the invention after the milling process with central pin 4, protective cap 10, implant-supported dental restoration part 8 and an external hex implant connection 14. This embodiment corresponds to a machined variant of the embodiment shown in FIG. 5. In this embodiment, the protective cap is sealed to the milled base body 2 of the partially finished milling blank by means of a design 34 such that it seals the protective cap against an undercut 33 of the partially finished milling blank. In order to prevent contamination of the interior of the protective cap by chips, dust or other impurities during the milling process, a so-called sovereign zone 46 is excluded from the milling process. In this embodiment example, this is flat, but a conical design that increases in thickness towards the centre is also conceivable. In addition to sealing the protective cap 10, this also enables it to be securely anchored by means of a special design 34 of the sealing lip. Such a sovereign zone 46 can be, for example, 0.2 mm thick. This zone of highness 46 is removed during finishing, for example by a dental technician using a hand cutter in a dental laboratory.
[0081] FIG. 8 shows a schematic representation of the manufacturing process of a dental restoration part as a digital process from a partially finished milling blank as a flow chart. For illustration purposes, the conventional process of manufacturing a dental restoration is shown in comparison.
LIST OF REFERENCE SIGNS
[0082] 1 Partially manufactured milling blank [0083] 2 base body [0084] 4 Central pin [0085] 5 pin counter element [0086] 6 excess areas [0087] 8 Implant-supported dental restoration part [0088] 10 Protective cap [0089] 12 Central canal or canal bore [0090] 14 External hex implant connection [0091] 16 Truncated cone [0092] 18 Face/front end [0093] 20 Base or end of truncated cone [0094] 22 Recess [0095] 24 Retaining element [0096] 26 Retaining extension [0097] 28 Internal hex implant connection [0098] 30 Tapered implant connection [0099] 32 Sealing lip [0100] 33 Undercut [0101] 34 Shaping [0102] 35 Highness/Sovereign zone [0103] 36 Thread fixation or thread [0104] 38 Friction fixation [0105] 42 Milling tip [0106] 44 Milling head [0107] 46 Highness/Sovereign zone
